Sphincter — Sphinc ter, n. [NL., fr. ??? to bind tight.] (Anat.) A muscle which surrounds, and by its contraction tends to close, a natural opening; as, the sphincter of the bladder. [1913 Webster] … The Collaborative International Dictionary of English

sphincter — ► NOUN Anatomy ▪ a ring of muscle surrounding and serving to guard or close an opening such as the anus. ORIGIN Greek sphinkt r, from sphingein bind tight … English terms dictionary

sphincter — [sfiŋk′tər] n. [LL &LT; Gr sphinktēr &LT; sphingein, to draw close &LT; IE * spheig &LT; base * spēi , to flourish, grow thick &GT; SPEED, SPARE] Anat. a ring shaped muscle that surrounds a natural opening in the body and can open or close it by… … English World dictionary

Sphincter — A sphincter is an anatomical structure, or a circular muscle, that normally maintains constriction of a natural body passage or orifice and which relaxes as required by normal physiological functioning. Sphincters are found in many animals; there … Wikipedia

sphincter — A muscle that encircles a duct, tube, or orifice in such a way that its contraction constricts the lumen or orifice. SYN: musculus s. [TA], s. muscle [TA]. [G. sphinkter, a band or lace] s. of ampulla s. of hepatopancreatic ampulla. anatomic s.… … Medical dictionary